Grizzly, although I've never driven one, by all accounts I've ever read the first year Boss 302's were a crap street engine. They made NO low rpm power and only ran at the top end of the RPM range. Ford downsized the intake valves and made the power more usable in the 2nd year of production.
If someone wants to duplicate the performance of a Boss 302 in a Y-Block you could max port a set of the new heads and put them on a 272 (BOSS-Y or Y-Boss ?). Now to really duplicate a Boss302 you would also need to over cam the thing to death, as the Bosses were. The cam would not run below 4500rpm even in a 351.
The factory tech in 1970 wasn't all that advanced. Ford didn't understand port velocity or chamber shape. In the 1990's there was a hugh market in the US for Australian 302 Cleveland heads because the 4bbl US Cleveland heads had too large intake ports and the 2bbl heads had a horrible, detonation prone chamber.
Making power doesn't just mean big ports, big carb, big cam. Also, street power is totally different from dragstrip power.
When I quote an engine job I give people a base price and tell them "every time you say I want the price goes up". Now if you know where to get parts for free you might be able to build a better engine at no additional cost. I have not yet figured out how to install forged pistons for the same price as cast, or how supply aftermarket rods at the same cost as re-using the originals. Last time I ordered from ARP they wanted a lot of money for their fasteners. In short, the more power and RPM you try to wring out of an engine the better the parts need to be in the engine if you want it to live. Higher RPM=Better parts=More money!
I'll bite my tongue now
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